It is an error if a class with one or more abstract methods is not explicitly declared abstract.
True
False
Correct Answer :
A. True
Related Questions
What does the following line of code do?
TextField text=new TextField(10);
Creates text object that can hold 10 rows of text.
Creates text object that can hold 10 columns of text.
Creates the object text and initializes it with the value 10.
The code is illegal.
Any class may be inherited by another class in the same package.
True
False
Which of the following statements are true?
UTF characters are all 24 bits.
Reader class has methods that can read integers and floats.
Unicode characters are all 16 bits.
all of the above
An EJB is a server-side component that encapsulates the business logic of an application
True
False
Servlet has ___________
init method
doGet(------) method
All of the above methods.
In a single Servlet class we can use____________
doGet(...) method only
doPost(...) method only
doGet(...) method and doPost(...) method both at a time.
Either 'a' or 'b'
If a=10 and b= 15, then the statement x =(a>b)?a:b; assigns the value 15 to x.
True
False
When present, package must be the first no comment statement in the file.
True
False
Which are the valid ways to create DataInputStream streams?
new DataInputStream(new File("in.dat"));
new DataInputStream(new FileInputStream("in.dat"));
new DataInputStream("in.dat");
new DataInputStream("in.data","r");
Consider the following class definitions:
class maths {
student student1;
}
class student {
String name;
}
student student1;
}
class student {
String name;
}
This code represents:
an 'is a' relationship
a 'has a' relationship
both
neither
A catch can have comma-separated multiple arguments.
True
False
The length of a string object 's1' can be obtained using the expression s1.length.
True
False
Objects are passed to a method by use of call-by-reference.
True
False
In RMI before running the client program we must start RMI Registry.
True.
False.
If a=10 and b= 15, then the statement x =(a>b)?a:b; assigns the value 15 to x.
True
False
A string object can not be modified after it is created.
True
False
When we invoke repaint () for a Component, the AWT invokes the method:
draw()
update()
show()
paint()
It is an error to catch the same type of exception in two different catch blocks associated with a particular try block.
True
False
The default case is always required in the switch selection structure.
True
False
executeUpdate automatically updates data because___________
auto commit is on, by default
It performs a hidden commit statement as well
Does not commit
None of the above.
What is error in the following class definitions?
abstract class xy {
abstract sum(int x, int y) {
}
}
abstract sum(int x, int y) {
}
}
class header is not define properly
constructor is no defined
method is not defined properly
no error
Which of the following methods belong to the String class?
length()
compareTo()
substring()
all of the them
All methods in an abstract class must be declared abstract.
True
False
Give file is a file object, which of the following are legal statements to create a new file.
file.create();
FileOutputStream fos=new FileOutputStream(file);
FileInputStream fis=new FileInputStream(file);
all of the above
It is an error to have a method with the same signature in both the super class and its subclass.
True
False
Which of the following keywords are used to control access to a class member?
default
protected
interface
None of the above
In order to connect to a database through java program we must create _______-
Connection, Statement, ResultSet
Connection, ResultSet
Statement< ResultSet
Connection, Statement
Every call to wait has a corresponding call to notify that will eventually end the wafting.
True
False
Which of the following will produce a value of 22 if x=22.9:
Ceil(x)
Round(x)
Rint(x)
Abs(x)
The name of a Java program file must match the name of the class with the extension Java.
True
False